1. Field of the Invention
The present invention relates to making tires. More specifically, the present invention relates to making foam core tires.
2. Discussion of Background
The use of foam in tires is not new. See for example U.S. Pat. Nos. 4,033,395, 3,952,786, 1,476,878 and 1,371,427. Foam filled or solid tires have several advantages over air-filled tires: punctures of such tires do not lead to a tire geometry and control as with air-filled tires. However, foam-filled tires have problems with slippage between foam and casing which can result in a material or geometric deterioration from friction at high speeds.
In the field of scale model vehicles, the selection of tires has been limited to solid tires made entirely of rubber, or a rubber material. Scale model, remotely-operated racing cars with such tires have difficulty holding curves above 40 miles per hour. Solid rubber tires, on such vehicles as riding lawn mowers do not give a smooth ride; air filled tires for such vehicles are relatively expensive because of the need to provide stability in the form of internal belts.
There is a need for a tire that provides the cushioning of air-filled tires but is unaffected by punctures and has good material and geometric stability at the speed of use.